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                                                                    EXHIBIT 31.1


                  CERTIFICATION OF THE CHIEF EXECUTIVE OFFICER
                         PURSUANT TO SECTION 302 OF THE
                           SARBANES-OXLEY ACT OF 2002

I, Gilles Gagnon, President and Chief Executive Officer of AEterna Laboratories
Inc., certify that:

     1.  I have reviewed this annual report on Form 40-F of AEterna Laboratories
         Inc.;

     2.  Based on my knowledge, this annual report does not contain any untrue
         statement of a material fact or omit to state a material fact necessary
         to make the statements made, in light of the circumstances under which
         such statements were made, not misleading with respect to the period
         covered by this annual report;

     3.  Based on my knowledge, the financial statements, and other financial
         information included in this annual report, fairly present in all
         material respects the financial condition, results of operations and
         cash flows of the registrant as of, and for, the periods presented in
         this annual report;

     4.  The registrant's other certifying officer and I are responsible for
         establishing and maintaining disclosure controls and procedures (as
         defined in Exchange Act Rules 13a-14 and 15d-14) for the registrant and
         have:

              a)  designed such disclosure controls and procedures to ensure
                  that material information relating to the registrant,
                  including its consolidated subsidiaries, is made known to us
                  by others within those entities, particularly during the
                  period in which this annual report is being prepared;

              b)  evaluated the effectiveness of the registrant's disclosure
                  controls and procedures as of a date within 90 days prior to
                  the filing date of this annual report (the "Evaluation Date");
                  and

              c)  presented in this annual report our conclusions about the
                  effectiveness of the disclosure controls and procedures based
                  on our evaluation as of the Evaluation Date;

     5.  The registrant's other certifying officer and I have disclosed, based
         on our most recent evaluation, to the registrant's auditors and the
         audit committee of registrant's board of directors (and persons
         performing the equivalent function):

              a)  all significant deficiencies in the design or operation of
                  internal controls which could adversely affect the
                  registrant's ability to record, process, summarize and report
                  financial data and have identified for the registrant's
                  auditors any material weaknesses in internal controls; and

              b)  any fraud, whether or not material, that involves management
                  or other employees who have a significant role in the
                  registrant's internal controls; and


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     6.  The registrant's other certifying officer and I have indicated in this
         annual report whether there were significant changes in internal
         controls or in other factors that could significantly affect internal
         controls subsequent to the date of our most recent evaluation,
         including any corrective actions with regard to significant
         deficiencies and material weaknesses.



/s/ GILLES GAGNON
-------------------------------------
Gilles Gagnon
President and Chief Executive Officer


Dated: May 17, 2004



A signed original of this written statement required by ss. 906 has been
provided to AEterna Laboratories Inc. and will be retained by AEterna
Laboratories Inc. and furnished to the Securities and Exchange Commission or its
staff upon request.